Synthesis and Reactivity of Transition Metal Hydrides

Michael Heinekey博士，华盛顿大学化学系，由无机化学、生物无机化学和有机金属化学项目支持，研究过渡金属氢化物的合成和反应性。将开发铁和钚的阳离子二氢络合物的合成方法。这些络合物将作为氢酶活性中心的模型进行研究。三吡唑基和相关配体将用于稳定一系列阳离子Ir和Rh氢化物，这些氢化物将用于活化烃。将研究多氢金属络合物中发生的量子力学质子隧穿的结构和电荷相关性，以增加对这一过程的机理理解。这项研究的很大一部分将涉及对氢化物的研究，其中已掺入了氚或氚。氚核磁共振将被用来表征其中一些系统的行为。交换耦合将作为发生在这些体系中的溶剂化和离子配对的探针来发展。在17.6特斯拉的强磁场下，将研究二氢络合物的部分取向，这些数据将被用来确定络合物中的H-H距离。当氢分子与金属原子相互作用时，它们可能被激活。这一行为在实验室和工业化学中具有巨大的实用价值，可以提高氢发生许多反应的能力，包括几乎所有的“氢化”反应。另一方面，随着人们对氢作为清洁燃料的兴趣增加，氢与金属之间的相互作用已成为一个重要的话题。在这个项目中，将研究氢与金属结合的基本方式，并确定氢原子如何相互交换并与周围环境相互作用的细节。

Dr. Michael Heinekey, Chemistry Department, University of Washington, is supported by the Inorganic, Bioinorganic, and Organometallic Chemistry Program for studies of the synthesis and reactivity of transition metal hydrides. Synthetic methods will be developed for cationic dihydrogen complexes of iron and ruthenium. These complexes will be studied as models for the active site of hydrogenase. Tris-pyrazolyl and related ligands will be used to stabilize a series of cationic Ir and Rh hydrides that will be used to activate hydrocarbons. Structural and charge dependence of the quantum mechanical proton tunneling that occurs in polyhydride metal complexes will be investigated to increase the mechanistic understanding of the process. A significant portion of the study will involve the study of hydrides into which deuterium or tritium has been incorporated. Tritium nmr will be used to characterize the behavior of some of these systems. Exchange coupling will be developed as a probe of the solvation and ion-pairing that occurs in these systems. The occurrence of partial orientation of dihydrogen complexes in very high magnetic fields will investigated at 17.6 Tesla and these data will be used to determine the H-H distance in the complexes. Hydrogen molecules may be activated when they interact with metal atoms. This behavior has tremendous utility in laboratory and industrial chemistry to increase the ability of hydrogen to undergo many reactions, including virtually all "hydrogenation" reactions. In another respect, the interactions between hydrogen and metals has become an important topic with the increased interest in hydrogen as a clean fuel. In this project the fundamental ways that hydrogen becomes attached to a metal will be investigated and the details of how hydrogen atoms interchange with each other and interact with the surrounding environment will be determined.